Question

I have an arraylist populated by four elements, the order of which is random (they are put here by random from another arraylist). I then have a for loop that repeats 10 times, at the end of each repetition I use the clear methods to clear all the elements of the arraylist. However, when I start a new repetition, I would like to repopulate my arraylist with the old (previously worked with) elements that were members of the list in the previous repetition, so that I can use the elements again. And I would like to repeat that until I get out of my 10-repetition for loop. Is there any way to achieve this at all?

Code in addition to my question:

 ArrayList<String> answerPegs =  new  ArrayList<String>();
  // add element to ArrayList

    ArrayList<String> mySecretAnswer = new ArrayList<String>();

    for (int n = 4; n > 0; n--) 
    {       
         //populate mySecretAnswer with elements from answerPegs
    }


    ArrayList<String> clone1 = mySecretAnswer;

    for (int q = 0; q < 10; q++) { 

        for (o = 0; o < 4; o++)
        {
         }
      // called clear() method here

    } // END OF 10-ROW LOOP

Answer 1

I would suggest simply having 2 lists – keep a pristine copy of the original list, and then iterate over + clear a copy of that list.

public void doRepetitions(List<Object> original)
{
    for( int i=0; i<10; i++ )
    {
        List<Object> working = new ArrayList<Object>( original );
        doStuffWithList(working);
    }
}

Edit:
Since you’ve posted your code, I can give a more specific answer:

You can change your clone to be:

ArrayList<String> clone1 = new ArrayList<String>(mySecretAnswer);

And then move that to be inside your for loop:

for (int q = 0; q < 10; q++)
{ 
    ArrayList<String> clone1 = new ArrayList<String>(mySecretAnswer);
    // ....
}